Yes, eggs without a stamp are safe to eat.
Some egg graders in Ontario stamp their eggs with a code that helps you access the best before date, even if you no longer have the carton. The code may also include an identification number that can be traced back to the grading station.
The stamp is approved by the Canadian Food Inspection Agency, so whether you’re boiling, scrambling, or cracking your eggs, you can be confident that the vegetable-based ink used is 100% food safe.